Question

Find the sum of the first 20 terms of the AP2+7+12+......by using formula

Answer 1

Answer:

AP- 2 7 12 ......

A(first term) 2

d= 7-2=5

n=20

s20=20/2 +(2(2)+(20-1)5

= 10+23×5

= 125..

Explanation:

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